Insulin—Blood Cardioplegia Decreases Matrix Metalloproteinase Activity in Ischaemia-reperfusion Injury during Coronary Artery Bypass Surgery

Reperfusion of myocardium during coronary bypass activates matrix metalloproteinases (MMPs) with changes occurring in the levels of tissue inhibitors of metalloproteinases (TIMPs) in the myocardium. This study investigated the effects of insulin-blood cardioplegia on MMP activity and TIMP levels during reperfusion. Non-diabetic patients undergoing coronary artery bypass graft with cardiopulmonary bypass were randomized into a control group ( n = 12) or an insulin group ( n = 12). Blood cardioplegia was used for both groups; insulin and glucose were added to the insulin group. Blood samples were obtained from the coronary sinus just before aortic cross clamping and after 1 and 30 min of reperfusion. Plasma proenzyme MMPs (proMMP-2 and −9) and TIMPs (TIMP-1 and TIMP-2) levels were measured. There were no differences between groups for MMP-2 and TIMP-2 levels. However, insulin diminished proMMP-9 activation, although some still occurred. TIMP-1 consumption lessened during reperfusion which, we conclude, was as a result of the diminished MMP activation. This is the first open heart surgery study in which diminished MMP activation was achieved via a metabolic change.

Surgical Management of Giant Aneurysms Complicating Arteriovenous Fistulae

The creation of an arteriovenous fistula (AVF) is frequently used to achieve easier access for haemodialysis in patients with chronic renal insufficiency. The most frequent late complication of AVFs is aneurysm formation, which carries the risk of spontaneous rupture. This study reports on 18 patients with giant aneurysms that developed on antebrachial AVFs who were operated on over a period of 6 years. Colour duplex ultrasonographic examination of the upper extremity was performed in all but one patient in the preoperative period.

Surgical management included resection of the aneurysm and re-establishment of arterial continuity. There were no complications such as infection, ischaemic extremity loss, neurological sequelae or mortality. Colour duplex ultrasonographic examinations after 6 months were all normal. The mean follow-up period was 29.1 months (range 7 − 50 months). There were no additional vascular complications observed during follow-up. Early surgical intervention is the recommended treatment of choice for giant aneurysm complicating antebrachial AVF.

Aortic ruptured following lung resection in invasive aspergillosis

Invasive pulmonary aspergillosis, although rare in the general population, can prove to be an important cause of morbidity and mortality in immunosuppressed patients. In this paper we represent a case of aortic rupture for a fungal invasion of the aorta after a pulmonary resection procedure. Although a few cases are documented in the literature, we report our experience to make our colleagues aware of this complication.

A new closure technique for limited thoracotomy where the ribs are spread minimally

An alternative closure technique for limited thoracotomy incisions is described below. This technique consists of fixing the intercostal muscles with horizontal mattress sutures. Also the described technique can be applied where the ribs are spread minimally in such limited thoracotomy incisions.

The role of autologous blood injection on postoperative air leak at lung resections

BACKGROUND

The effects of autologous blood injection beneath the stapling lines on postoperative air leak after lung resections, especially in emphysematous lungs, were prospectively investigated.

METHODS

The study was carried out on 16 randomized patients. The mean age of the study group was 58 and the mean forced expiratory volume at one second (FEV1) at the spirometry was 2.05 L. In the control group, the mean age was 60 and the mean FEV1 was 1.97 L. All 16 cases were males and had a history of smoking. In the study group, 10-20 ml of autologous venous blood was drawn by the anesthesist and transferred to the operation team. The blood was gently injected underneath the staple line and ultimately 1 cm thickened layer of the lung was obtained. In the control group only staplers were applied.

RESULTS

There was no air leak at the end of the operation at the study group, whereas additional sutures which were pledgetted with Gore-tex patches were needed at four cases at the control group. There were minimal air leaks at three cases at the control group at the postoperative period, while there was no postoperative air leak problem at the study group. Thorax tubes were removed at the 3rd and the 3.9th days at the study and the control groups, respectively.

CONCLUSIONS

We believe this simple and cheap method could be used at least in some instances where additional staple reinforcement would be necessary. It may also be remembered when air leaks are encountered at suture holes after suturing the lung.

Transthoracic colour Doppler ultrasonography in the evaluation of internal thoracic artery bypass graft patency

The internal thoracic artery (ITA) is the most important conduit for coronary artery bypass grafting. The quality of the anastomosis joining the ITA to the left anterior descending coronary artery has a major impact on left ventricular perfusion. The rapid detection of flow disturbances due to sub-optimal anastomosis is, therefore, of great prognostic significance. In this study, 47 coronary bypass patients were examined using colour Doppler ultrasonography peri-operatively and 4-6 months post-operatively. Findings were correlated with clinical observations and a treadmill exercise test. The pre-operative ITA flow pattern was normally triphasic, but changed post-operatively to simulate the normal biphasic flow pattern of left anterior descending coronary artery. A 35-case-control group was used to compare pre-operative ITA flow characteristics. The authors conclude that Doppler parameters, clinical findings and the treadmill test can be used in combination for the routine evaluation of graft patency, and to select cases that require more invasive coronary angiography.

Cost-effectiveness of minimally invasive-intervention in aortofemoral revascularization

Minimally invasive surgical procedures have become popular recently because they offer several advantages over conventional operative techniques. A person undergoing a minimally invasive procedure usually experiences less pain, is discharged earlier from hospital, returns to work sooner and has a less obtrusive post-operative scar. Excluding highly technical techniques (e.g. laparoscopic surgery), operations performed using mini-laparotomy are usually more cost-effective than conventional procedures, largely because they are less expensive to perform. Our paper investigates cost-effectiveness and other parameters relating to minimally invasive aortofemoral revascularization procedures performed at our clinic. We compared 20 similar cases, half where revascularization was undertaken using mini-laparotomy and half where conventional laparotomy was selected. From our findings we conclude that mini-laparotomy is safe and reliable for aortobifemoral bypass procedures and has several advantages over traditional techniques; namely, shorter operating time, earlier resumption of intestinal function, shorter duration of in-patient stay and reduced costs.

A new minimally invasive method of aortofemoral revascularization

In recent years, minimal invasive surgical applications have been used in every field of surgery and became a routine application for some kinds of operations. Mini-laparotomy has been limited to abdominal incisions between 3 and 10 cm long. Four aortobifemoral and one aortofemoral bypass cases that were performed with mini-laparotomy incision between January 1997 and February 1998 are presented. In all cases, revascularization of lower extremities was performed successfully without enlarging the incision. The average operation time was shorter and the number of transfused blood units was significantly lower in that group when compared to the conventional laparotomy group of 12 cases. In all cases, bowel sounds appeared in 2 to 8 hours and at the end of 24 hours, oral nutrition was started. The mean discharge time from the hospital was 4.7 days. With the advantages of less operation time, optimal aortic exposure, ability in safe cross-clamping, less postoperative pain, less scar tissue occurrence, early resumption of intestinal functions, early mobilization and shorter hospitalization time, the mini-laparotomy technique is a safe reliable method for use in aortobifemoral bypass operations.

Retrograde cerebral perfusion with hypothermic circulatory arrest in a child

This report describes a 4-year-old boy who presented with infective endocarditis involving the ascending aorta and the arch vessels, with supravalvular aortic stenosis as the underlying pathology. Operation was indicated because of the embolic potential of the vegetations inside the aorta. Retrograde cerebral perfusion was utilized in conjunction with hypothermic circulatory arrest, to flush particulate materials from the arch vessels during operation.

Lung-volume reduction in parallel with coronary heart surgery: a case report

For patients with severe disabling emphysema, lung-volume reduction surgery has recently been introduced as an alternative to transplantation. Performing parenchyma resection from appropriate areas can improve pulmonary functions in selected patients having severe emphysema with a flattened diaphragm. We report the case of a patient, who urgently needed coronary revascularization and was otherwise inoperable because of severe chronic obstructive pulmonary disease (COPD). We carried out lung-volume reduction surgery at the same time as the coronary bypass.

Ligation of patent ductus arterious by the method of video-assisted thoracoscopic surgery and our other VATS experiences

In April and May 1996, two cases of PDA ligation were performed firstly in Turkey by the method of video assisted thoracoscopic surgery (VATS) in Dokuz Eylül Medical Faculty, Thoracic and Cardiovascular Surgery Department. There was not any complication in these patients in the postoperative period and they were discharged on the second day in symptom-free condition by the detection of closed ductus in their echocardiographic examination. Between February 1993 and October 1996, a total of 46 patients have undergone interventional application by VATS. While in six of these patients the procedure could not be manipulated because of massive pleural fibrosis, there was no mortality or morbidity among the patients, and they were discharged on average on the second day. The ratio of complications, such as bleeding, air leak, arrhythmia and empyema are so low in these operations, and hospital stay, with return to work time are shorter than with the open technique.

Nisoldipine Cardioplegia in the Isolated Rabbit Heart

BACKGROUND: The metabolic and hemodynamic effects of nisoldipine supplementation in cardioplegia after ischemic injury were investigated in 13 isolated rabbit hearts. Group 1 consisted of 6 hearts, which received St. Thomas II cardioplegic solution. In group 2, nisoldipine was added to the cardioplegic solution at a concentration of 0.1 mg/kg in 7 hearts. METHODS: The explanted hearts were suspended from Langendorff apparatus and were perfused with Krebs-Henseleit solution. Left ventricular pressure, heart rate, malondialdehyde, glutathione peroxidase, glutathione reductase, reduced glutathione, oxidized glutathione, creatine kinase MB, (CK-MB), aspartate transaminase, and lactate dehydrogenase (LDH) were measured before and after 60 minutes of ischemia. Peak generated pressure after ischemia was significantly higher in group 2 versus group 1 while end-diastolic pressure was significantly lower in group 2 after ischemic arrest (P <.05). RESULTS: Malondialdehyde levels were lower in group 2 (P <.05). Glutathione peroxidase and glutathione reductase levels were significantly higher in group 2 (P <.05). The only enzymatic significant difference was observed between the preischemic and postischemic levels of aspartate transaminase in group 2 (P <.05). CONCLUSIONS: These findings show beneficial effects of nisoldipine cardioplegia, although its use as a cardioplegic additive is not yet possible. We believe, however, the effects of oral nisoldipine before cardiac surgery can be studied in a clinical setting.

A comparison of digoxin concentration--time curves before and after open-heart surgery

The effects of open heart surgery on serum digoxin concentration--time curves were investigated in 10 cardiac patients receiving 0.25 mg/day digoxin. Blood samples were obtained from the patients immediately before and 1, 2, 3, 5, 8, 16 and 24 h after digoxin administration, both before open-heart surgery and 7 days after surgery. Serum digoxin concentrations, determined by fluorescence polarization immuno-assay, significantly (P < 0.05) increased after surgery, as did the maximum serum concentrations and the areas under the concentration-time curves. After surgery there was a significant increase in the serum gamma-glutamyl transferase concentration and a significant reduction in the total protein concentration. A reduction of digoxin dose may be appropriate for patients who have undergone open-heart surgery.